This patch series consolidates the backend cpuidle driver for pSeriesand powernv platforms with minimal code duplication.

Current existing backend driver for pseries has been moved to drivers/cpuidle and has been extended to accommodate powernv idle power mgmt states. As seen in V1 of this patch series, having a separate powernv backend driver results in too much code duplication, which is less elegant and can pose maintenance problems going further.

Using the cpuidle framework to exploit platform low power idle statesmanagement can take advantage of advanced heuristics, tunables and features provided by framework. The statistics and tracing infrastructure provided by the cpuidle framework also helps in enabling power management related tools and help tune the system and applications.

Earlier in 3.3 kernel, pSeries idle state management was modified to exploit the cpuidle framework and the end goal of this patch is to have powernvplatform also to hook its idle states into cpuidle framework with minimal code duplication between both platforms.

This series aims to maintain compatibility and functionality to existing pseries and powernv idle cpu management code. There are no new functions or idle states added as part of this series. This can be extended by adding more states to this existing framework.

With this patch series, the powernv cpuidle functionalities are on-par with pSeries idle management.

* Make backend driver a built-in, instead of a module. As building this as a module is currently not possible.

* Generic backend driver minor cleanups.

* First two patches in V5 are not a part of the series, as they are generic cleanups, already pushed into the tree.

Changes in V5:=============

* As per the discussions in the community, this patch series enables cpuidle backend driver only for IBM-POWER platforms. File is re-named from drivers/cpuidle/cpuidle-powerpc.c to drivers/cpuidle/cpuildle-ibm-power.c New back-end cpuidle driver is called IBM-POWER-Idle.

* General cleanups on the accessors front that was introduced in previous version.

* This patch series does not include smt-snooze-delay fixes. This will be taken up later on.

* Integrated POWERPC driver in drivers/cpuidle. Enabled for all of POWERPC platform. Currently has PSERIES and POWERNV support. No compile time flags in .c file. This will be one consolidated binary that does a run time detection based on platform and take decisions accordingly.

* Enabled CPUIDLE framwork for all of PPC64.

Changes in V2:=============

* Merged the backend driver posted out for powernv in V1 with pSeries to create a single powerpc driver but this had compile time flags.